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Another SET 2A3 in the world

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After a whole year slowly gathering parts all over the world and slowly working (don't have enough time for this), I have finished my first SET 2A3 amp, following the wonderful JE Labs web site

http://members.myactv.net/~je2a3/se300b.htm

The schematic I chose was the stereo SE2A3dx with the James 6123HS outputs

I want to thank you all in the forum who are sharing so much knowlegde and have allowed me, with no experience in this, to be able to build such an amp. I'm not an expert, but it sounds wonderfully. No hum at all (1mV in the output) and power more than enough to make my Dallas II horn enclosures shout.
Only one question: the tubes I am using are 2A3 Sovteks, RCA 6SN7 and Sylvania 76. Is it worth buying better tubes of other brands in order to improve the sound even more? Which ones ?

Thank you very much again


lquintas
 

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Wow, very nice! Did you cut the wood for the chassis yourself, or did you buy it? Are those Jensen Oil caps I see in there?

I have found Most RCA and Sylvania tubes to be very good. As far as Sovteks go, there have been some I really like and some that are just ok. That is a general statement as I've never worked with thier 2A3's.
 
You did a excellent job. I too am building the JE Labs 45 w/ James 6123,My 1st amp & should be up in smoke or singing by tommorrow evening. If I succed, then I will try the 300B version. I know one thing the qulity of the James OT's surpised the heck out of me, I hope they sound as good as they are built. I like the way you mounted your ASC motor runs. I think I will steal that trick, mounting the clamp upside down w/ no visible clamp up top. I like it... Have you tried any other taps..? I went ahead & solder 4-8- & 16 just so I can try them.
 
Congrats and nice work!

I also have a JE Labs 2A3 DX and use an all RCA tube complement (76, 6SN7, bi-plate 2A3, 5U4G). The Sovtek is value for money IMHO, I started with that too. The Sylvania 76 is also good as well as the National Union.

I use MagneQuest OPT in mine, the DS-025, but my experience with James says they're very good too. I'm currently using a James JS-6113HS for my 300B.
 
I liked how the schematic was complete and the suggested iron was on the page, made the build easier. I had no tube guru near by or a good amp meter :whazzat: so I wasn't ever sure if I had it right :) But once it successfully produced music I concidered the who thing a success. I'm going with a 12b4a pre and a pair of mono-blocks next; maybe the PP-C1, or something from dynakit, or maybe the Baby heuy or el-cheapo. But the JE-labs stuff was a good start.
 
Thank you very much for your comments. I didn't have any tube guru either, but I learnt a lot from your posts, athos56, arnoldc and others! As the amp worked correctly at the first try, I havn't tried anything else. I'm specially proud of the low hum level (my first tube amp, a EL84 SET, hummed a lot) as I have followed the advice of SY and others concerning the ground (see the attached file), arranging the wires as if they were water pipes (I undestand hydraulics better than electronics)
 

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The speakers I use are Fostex 206e mounted in Ron Clark's Dallas II horn enclosures, difficult to build, but perfect for this kind of amp. In the Fostex I installed the phase plugs I bought to you, planet10, with very good results (better mids).
 

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lquintas said:
Thank you very much for your comments. I didn't have any tube guru either, but I learnt a lot from your posts, athos56, arnoldc and others! As the amp worked correctly at the first try, I havn't tried anything else. I'm specially proud of the low hum level (my first tube amp, a EL84 SET, hummed a lot) as I have followed the advice of SY and others concerning the ground (see the attached file), arranging the wires as if they were water pipes (I undestand hydraulics better than electronics)

He helped me like that as well, SY always has good advice, as do many other people here. I still only understand 1/4th of what I read. I really like the polished top and wood frame look, I'm going to try and find a place that sells copper, or some other metal, sheets. I only had a bit of crackly static in mine that might have come from the reciever I had it hooked up to. Also, I really like those speakers! I'm building some monkey coffins right now :D myself, you've got me itch'n to finish.
 
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